一台Exadata。需要访问github上的资源。以下简要描述其过程。
首先确认域名解析正常，这个是设置在/etc/resolv.conf中的：
$ nslookup www.google.com
Server: xxx.xxx.xxx.xxx
Address: xxx.xxx.xxx.xxx#53Non-authoritative answer:
Name: www.google.com
Address: 142.250.183.4
Name: www.google.com
Address: 2404:6800:4009:820::2004
由于Exadata要通过代理才能访问外网，因此yum需要配置代理，在/etc/yum.conf文件中，添加以下语句：
proxy=http://xxx.xxx.xxx.xxx:80
但是，yum search报错：
$ yum search git
Oracle Linux 8 BaseOS Latest (x86_64) 0.0 B/s | 0 B 00:01
Errors during downloading metadata for repository 'ol8_baseos_latest':- Curl error (60): Peer certificate cannot be authenticated with given CA certificates for https://yum$ociregion.$ocidomain/repo/OracleLinux/OL8/baseos/latest/x86_64/repodata/repomd.xml [SSL certificate problem: unable to get local issuer certificate]
Error: Failed to download metadata for repo 'ol8_baseos_latest': Cannot download repomd.xml: Cannot download repodata/repomd.xml: All mirrors were tried
应该是repository地址设置有误。
查看所有repo信息：
$ dnf repolist
repo id repo name
docker-ce-stable Docker CE Stable - x86_64
nginx-mainline nginx mainline repo
nginx-stable nginx stable repo
ol8_UEKR6 Latest Unbreakable Enterprise Kernel Release 6 for Oracle Linux 8 (x86_64)
ol8_UEKR7 Latest Unbreakable Enterprise Kernel Release 7 for Oracle Linux 8 (x86_64)
ol8_addons Oracle Linux 8 Addons (x86_64)
ol8_appstream Oracle Linux 8 Application Stream (x86_64)
ol8_baseos_latest Oracle Linux 8 BaseOS Latest (x86_64)
[ol8_baseos_latest]
name=Oracle Linux 8 BaseOS Latest ($basearch)
baseurl=https://yum$ociregion.$ocidomain/repo/OracleLinux/OL8/0/baseos/base/$basearch/
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-oracle
gpgcheck=1
enabled=1
果然，baseurl设置有问题，改为以下就好了：
https://yum.oracle.com/repo/OracleLinux/OL8/baseos/latest/$basearch/
git可以安装了：
$ sudo yum install git -y
Oracle Linux 8 BaseOS Latest (x86_64) 13 kB/s | 4.3 kB 00:00
Oracle Linux 8 Addons (x86_64) 11 kB/s | 3.5 kB 00:00
Latest Unbreakable Enterprise Kernel Release 7 for Oracle Linux 8 (x86_64) 11 kB/s | 3.5 kB 00:00
Dependencies resolved.
=======================================================================================================================================Package Architecture Version Repository Size
=======================================================================================================================================
Installing:git x86_64 2.43.5-1.el8_10 ol8_appstream 91 k
Installing dependencies:git-core x86_64 2.43.5-1.el8_10 ol8_appstream 11 Mgit-core-doc noarch 2.43.5-1.el8_10 ol8_appstream 3.1 Mperl-Error noarch 1:0.17025-2.el8 ol8_appstream 46 kperl-Git noarch 2.43.5-1.el8_10 ol8_appstream 78 kperl-TermReadKey x86_64 2.37-7.el8 ol8_appstream 40 kTransaction Summary
=======================================================================================================================================
Install 6 PackagesTotal download size: 14 M
Installed size: 46 M
Downloading Packages:
(1/6): git-2.43.5-1.el8_10.x86_64.rpm 163 kB/s | 91 kB 00:00
(2/6): perl-Error-0.17025-2.el8.noarch.rpm 518 kB/s | 46 kB 00:00
(3/6): perl-Git-2.43.5-1.el8_10.noarch.rpm 890 kB/s | 78 kB 00:00
(4/6): perl-TermReadKey-2.37-7.el8.x86_64.rpm 444 kB/s | 40 kB 00:00
(5/6): git-core-doc-2.43.5-1.el8_10.noarch.rpm 2.9 MB/s | 3.1 MB 00:01
(6/6): git-core-2.43.5-1.el8_10.x86_64.rpm 6.5 MB/s | 11 MB 00:01
---------------------------------------------------------------------------------------------------------------------------------------
Total 8.4 MB/s | 14 MB 00:01
Running transaction check
Transaction check succeeded.
Running transaction test
Transaction test succeeded.
Running transactionPreparing : 1/1Installing : git-core-2.43.5-1.el8_10.x86_64 1/6Installing : git-core-doc-2.43.5-1.el8_10.noarch 2/6Installing : perl-TermReadKey-2.37-7.el8.x86_64 3/6Installing : perl-Error-1:0.17025-2.el8.noarch 4/6Installing : perl-Git-2.43.5-1.el8_10.noarch 5/6Installing : git-2.43.5-1.el8_10.x86_64 6/6Running scriptlet: git-2.43.5-1.el8_10.x86_64 6/6Verifying : git-2.43.5-1.el8_10.x86_64 1/6Verifying : git-core-2.43.5-1.el8_10.x86_64 2/6Verifying : git-core-doc-2.43.5-1.el8_10.noarch 3/6Verifying : perl-Error-1:0.17025-2.el8.noarch 4/6Verifying : perl-Git-2.43.5-1.el8_10.noarch 5/6Verifying : perl-TermReadKey-2.37-7.el8.x86_64 6/6Installed:git-2.43.5-1.el8_10.x86_64 git-core-2.43.5-1.el8_10.x86_64 git-core-doc-2.43.5-1.el8_10.noarchperl-Error-1:0.17025-2.el8.noarch perl-Git-2.43.5-1.el8_10.noarch perl-TermReadKey-2.37-7.el8.x86_64Complete!
成功克隆github项目：
$ git clone https://github.com/oracle-livelabs/cloud-database-services.git
Cloning into 'cloud-database-services'...
remote: Enumerating objects: 1931, done.
remote: Counting objects: 100% (715/715), done.
remote: Compressing objects: 100% (527/527), done.
remote: Total 1931 (delta 239), reused 584 (delta 165), pack-reused 1216 (from 1)
Receiving objects: 100% (1931/1931), 488.05 MiB | 17.44 MiB/s, done.
Resolving deltas: 100% (407/407), done.
Updating files: 100% (1375/1375), done.
